Stroke & TIA (Clinical)
Time is brain: separate ischemic from hemorrhagic, then hit the windows and targets
First steps: ischemic or hemorrhagic?
Stroke is a sudden focal neurologic deficit, ischemic in ~87% (thrombotic or embolic occlusion) and hemorrhagic in ~13% (vessel rupture). The clock starts at the last-known-well time, not when symptoms are discovered.
Non-contrast head CT first. The immediate test is a NON-contrast CT to exclude hemorrhage before any thrombolytic: blood appears bright immediately, whereas early ischemia is often CT-occult. Check a fingerstick glucose at the same time, because hypoglycemia mimics stroke, as can a seizure with postictal (Todd) paralysis or complicated migraine. CT angiography identifies large-vessel occlusion; MRI diffusion-weighted imaging is the most sensitive test for acute infarction but must not delay treatment.
NIH Stroke Scale (0–42). The NIHSS scores level of consciousness, gaze, visual fields, motor, sensory, language, and neglect. Higher scores mean larger, more disabling strokes and help select and follow reperfusion candidates; a high score with cortical signs (aphasia, neglect, gaze deviation) suggests a large-vessel occlusion amenable to thrombectomy.
Acute ischemic stroke: reperfusion and blood pressure
- Non-contrast CTExclude hemorrhage.
- IV thrombolysisWithin 4.5 h of last-known-well, if eligible; later only in imaging-selected patients.
- ThrombectomyLarge-vessel occlusion, up to 24 h with a favorable perfusion mismatch.
- Antiplatelet plus statinStart after 24 h when thrombolysis was given.
IV thrombolysis with alteplase or tenecteplase is given within 4.5 hours of last-known-well to eligible patients. Beyond 4.5 hours (including wake-up stroke), selected patients can still receive it when MRI shows a DWI-FLAIR mismatch or perfusion imaging shows salvageable penumbra. Contraindications include:
- Hemorrhage on CT, or active internal bleeding
- BP >185/110 that cannot be lowered
- Recent surgery or GI bleeding
- INR >1.7 or platelets <100,000
- Ischemic stroke or serious head trauma within 3 months
Mechanical thrombectomy treats large-vessel occlusion (internal carotid, MCA M1). Within 6 hours, vessel imaging is enough to select patients; from 6 to 24 hours from last-known-well, patients with a small core and large penumbra on perfusion imaging still benefit (DAWN, DEFUSE-3). It is performed with or after thrombolysis, not instead of it, when both apply.
| Scenario | Target | Why |
|---|---|---|
| Before thrombolysis | Lower to <185/110 | Limit bleeding risk |
| 24 hours after thrombolysis | Keep <180/105 | Prevent hemorrhagic transformation |
| Ischemic stroke, no thrombolysis | Permissive; treat only if >220/120 | Preserve penumbral perfusion |
| Intracerebral hemorrhage | Lower SBP toward ~140 (INTERACT2) | Limit hematoma expansion |
Supportive care. Screen swallowing before oral intake, treat fever and hyperglycemia, avoid hypoglycemia, and give DVT prophylaxis. Patients who did not receive thrombolysis start aspirin within 24–48 hours. A large MCA infarct with malignant edema may need decompressive hemicraniectomy.
Hemorrhagic stroke
Intracerebral hemorrhage. Hypertensive bleeds occur in the basal ganglia, thalamus, pons, and cerebellum; lobar bleeds in the elderly suggest cerebral amyloid angiopathy. Reverse any anticoagulation (warfarin: vitamin K plus 4-factor PCC), lower SBP toward ~140, control ICP, and involve neurosurgery; cerebellar hemorrhage compressing the brainstem or causing hydrocephalus needs evacuation. Thrombolytics and antithrombotics are contraindicated.
Subarachnoid hemorrhage presents with a thunderclap headache, usually from a ruptured aneurysm. Obtain a non-contrast CT; if it is negative, perform an LP for xanthochromia; then angiography locates the aneurysm for coiling or clipping. Nimodipine reduces delayed cerebral ischemia from vasospasm, which typically appears 3–14 days after the bleed. Watch for rebleeding, hydrocephalus, and hyponatremia.
TIA and the source workup
TIA is a warning, not benign. A TIA is a transient focal deficit WITHOUT infarction on imaging (a tissue-based definition). Early stroke risk is high, so it warrants urgent workup and secondary prevention, often within 24–48 hours.
| Component | Criterion | Points |
|---|---|---|
| Age | ≥60 years | 1 |
| Blood pressure | ≥140/90 | 1 |
| Clinical: weakness | Unilateral weakness | 2 |
| Clinical: speech | Speech disturbance without weakness | 1 |
| Duration | ≥60 min / 10–59 min | 2 / 1 |
| Diabetes | Present | 1 |
Hunt the source. Every stroke or TIA needs carotid imaging (duplex ultrasound or CTA), an ECG and telemetry for atrial fibrillation, and echocardiography for cardiac thrombus or shunt, plus glucose, lipids, and A1c. Prolonged ambulatory rhythm monitoring can capture paroxysmal atrial fibrillation missed on a single ECG in cryptogenic stroke.
Secondary prevention
Non-cardioembolic stroke or TIA. Give an antiplatelet (aspirin, clopidogrel, or aspirin-dipyridamole), a high-intensity statin (atorvastatin 80 mg), and BP control. After a minor stroke or high-risk TIA, short-term dual antiplatelet therapy (aspirin plus clopidogrel), started within 24 hours and given for ~21 days, reduces recurrence (CHANCE/POINT), followed by a single agent.
Atrial fibrillation means anticoagulate. Cardioembolic stroke from AF is prevented with anticoagulation, NOT antiplatelets. A DOAC (apixaban, rivaroxaban) is preferred over warfarin in nonvalvular AF; warfarin is required for mechanical valves or moderate-to-severe mitral stenosis. Infarct size guides when to start, since large infarcts carry more risk of hemorrhagic transformation.
Carotid endarterectomy. For symptomatic stenosis of 70–99% ipsilateral to the deficit, endarterectomy clearly benefits, ideally within 2 weeks; at 50–69% it benefits selected patients. A 100% occluded carotid is NOT revascularized.
Match the side: left-arm symptoms with an 80% right internal carotid stenosis mean a symptomatic right carotid, treated with right-sided endarterectomy.
Localizing by vascular territory
| Territory | Deficits |
|---|---|
| MCA | Contralateral face and arm weakness > leg; aphasia (dominant hemisphere) or neglect (nondominant); eyes deviate toward the lesion |
| ACA | Contralateral leg > arm weakness |
| PCA | Contralateral homonymous hemianopia, often with macular sparing |
| Lacunar (internal capsule, pons) | Pure motor or pure sensory deficit without cortical signs |
| Lateral medulla (Wallenberg, PICA) | Crossed sensory loss, ipsilateral Horner syndrome, dysphagia, hoarseness, vertigo, ataxia |